Sequencing revealed rare variants in genes involved in the IL-12-IFN-γ axis in several Th2-skewed patients, and we validated one such variant in IFNGR1 as hypomorphic.<h4>Conclusion</h4>Patients with DCM, especially males, should be screened for Th2 skewing of CD4+ T cells. This evidence concerns the gene CD4 and familial dilated cardiomyopathy.